Device for heating paraffin in oil wells



Dec. 7, 1943. A. w. PICK DEVICE FOR HEATING PARAFFIN IN OIL WELLS 4Sheets-Sheet 1 Filed Nov. 15, 1940 INVENTOR. A IMP/ck ATTORNEY.

Dec. 7, 194-3. A.'w. PICK DEVICE FOR HEATING PARAFFIN IN OIL WELLS FiledN06. 15, 1940 4 Sheets-Sh eet 2 IIDIIVENTOR. A M P: c/fi ATTORNEY.

Dec. 7,1943. A.'w. PicK DEVICE FOR HEATING PARAF'FIN IN OIL WELL$Filed/Nov. 151940 4 Shee'ts-Sheet 3 4 H: mm mm am, 6 M. o G W wll 9W RN7 a m V\ ATTORNEY.

Patented Dec. 7, 1943 DEVICE FOR HEATING PARAFFIN IN OIL WELLS Alfred W.Pick, Denver, 0010., assignor, by mesne assignments, to I. C. Miller,Denver, 0010.

Application November 15, 1940, Serial No. 365,760

2 Claims.

My invention relates to a device for heating paraffin in oil wells.

Many petroleum or oil wells deliver parainn with the oil, and in manysuch wells the parafiin is deposited out of the oil in the well, and inmore or less solid form.

Whether this deposited paraflin is deposited in the openings, amongstthe grains, or in the fissures, crevasses, faults, or interstices of therock surrounding the lower end of the well, or is deposited on the pumprods, or inside of the pump pipes, the final result in all cases is muchthe same; that is, the deposited paraflin decreases the oil productionof the well.

Various schemes have been tried to eliminate this paraffin fromproducing wells. Among these schemes is the use of heat from hotinternal combustion engine exhaust gases that are passed down what maybe called a U-tube, or return tube, that extends down into the ,well toa position adjacent the bottom thereof. This scheme so far has worked ina rather unsatisfactory way; for the results are limited by lack ofproper means to force enough hot exhaust gas at high enough temperature,through the U-tube to sufficiently heat the oil in the well and to heatat least portions of the surrounding rock.

In order to clean a well of paraflin enough heat must be carried downinto the well to so soften the paraffin that it will be sufficientlydissolved in the oil so that it will be pumped out of the well with theoil.

Though the exhaust gas from an internal combustion engine has been usedin this connection, and though some faint signs of promise have beennoted, it is difficult to provide, in such a way, enough hot gas and gasof high enough temperature to properly heat the oil well as it should beheated for the results desired; that is for the removal of the paraflinwith the pumped oil.

The object of this invention is to provide a new device for forcing morehot gas, at a higher temperature, through the U-tube in the oil well,and thereby provide better heating results in the oil Well.

I attain thisobject as follows: Instead of the explosive mixture beingcompletely exploded in an engine cylinder, and then passed out of theexhaust pipe, and hence the heat of the explosion of the explosivecharge is shot directly down the U-tube in the well Without being cooledby the water jacket of the engine cylinder during the slight timerequired in passing out of the engine cylinder after the explosion hasoccurred; and the force of the explosion is used directly to providespeedy transit of the hot burning gas through the U-tube.

Also, the U-tube is kept under a slight vacuum by means of a suctiondevice which tends to keep the gas in the U-tube moving continuouslyeven between the said explosions in the exhaust pipe. That is, theexplosive mixture is first drawn into an engine cylinder, and the bulkof said mixture is forced, still un-exploded, into the exhaust pipe; theremainder of the explosive mixture that was sucked into the engine, isthen compressed and exploded in the engine cylinder by a properly timedelectric spark, and the fire of the resulting explosion of this smallfraction of the entire explosive charge, passing out of the cylinder andinto the exhaust pipe, explodes the main bulk of the explosive chargewhich was previously forced out into the exhaust pipe; and thisexplosion in the exhaust pipe shoots directly down the U-tube and upthrough the return tube and out of the well, thus heating the U-tube andthe oil well by the direct heat of the explosion, so that the paraffinwill become soft and easily dissolved in the oil (of the well) which isbeing pumped to the surface of the ground.

I employ my special design of internal combustion engine, which may bebriefly described as follows: The intake. valve is not .mechanicallyoperated but is of the automatic suction-operated, spring-held, type,and to which is properly attached a gasolene or some kind of fuelcarburetor, properly adjusted to provide an explosive mixture as thecharge of air is sucked into the engine cylinder through the carburetorand the intake valve. r

The exhaust valve also is not mechanically operated, but is of theautomatic, spring-held type, and it opens outwardly, and not inwardly asis usual. That is, the exhaust valve opens in the opposite direction tothe opening of ordinary four cycle engine exhaust valves.

The exhaust valve is not located in the cylinder head, or above thepiston travel, as is usual,

but it connects with a port inthe cylinder wall,

keep the piston rings from springing out into the port.

The operation of my special type engine is as follows:

On the suction stroke, the piston sucks in a full charge of explosivemixture of air and fuel, through the intake valve and carburetor, thesuction of this suction stroke acting to pull the exhaust valve morefirmly down upon its seat during the entire suction stroke.

As the piston returns it begins to compress the explosive mixture thencontained in the cylinder, and as soon as this compression is greatenough to force open the exhaust valve against the action of the lightxhaust valve spring, the unexploded explosive mixture in the cylinderbegins to be forced through the exhaust valve out of the cylinder andinto the exhaust passages and pipe.

When the piston approaches the end of the compression stroke, it beginsto. cover the exhaust port in the cylinder wall, and finally covers theexhaust port completely, and the further slight movement of the pistonslightly compresses the remanent of the explosive mixture that istrapped in the cylinder above the exhaust port.

When the timed electric spark takes place at the spark plug, thistrapped remanent of the explosive charge, since it is under compression,explodes, and the fire of the explosion, (as the piston moves downwardand uncovers the exhaust port in the cylinder wall,) passes out throughthe exhaust valve and explodes the main bulk of the unexploded explosivecharge which had formerly been forced through the exhaust valve and intothe exhaust passages and the exhaust pipe.

Thus, the main explosion takes place right in the exhaust passages andthe exhuast pipe and down into the U-tube, with the speed and force ofthe explosion acting to drive a great amount of heat and the actual fireof the explosion quickly through the U-tube.

If the oil well is dry, the U-tube may be replaced by a single pipe thatextends down into the well and, whose open end terminates adjacent thebottom of the well.

If there is oil in the well, this single pipe should not be submerged,at its open end to a greater depth than the force of the explosions canovercome, that is, the force of the explosions should still be able toovercome the hydro-static pressure to such an extent as to permitexhaust to take place up through the oil or water in the well. Thus theheat will be allowed to. be quickly taken down into the well to properlyheat the parafiln.

All of the above will be more clearly seen and appreciated by referenceto the drawings, in which:

Figure 1 is a side View of my device mounted upon a truck and connectedby a chain to be driven by a power take-01f of the truck, and showingportions of a U-tube in the well and connected to my device.

Figure 2 is an end elevation showing the con nections and with portionsof the U-tube in the well.

Figure 3 is a detail of a modified form of U-tube, return tube, whichmay be used in place of the U-tube construction shown in Figures 1 and2.

Figure 4 is a view on the line 4-4 of Fi u e 3.

Figure 5 is a side view in partial section of my special form ofinternal combustion engine.

Figure 6 is an end view, but without the exhaust pipes.

Figure '7 is a view of my device, from above, in partial section.

Figure 8 is a section on the line 88 of Figure 2.

In Figure 1 my special form of engine is illustrated at I, mounted upona truck 2. An exhaust pipe 3 from the engine is connected to a down pipe4 of a, U-tube which, adjacent the bottom of the well, connects to areturn bend 5 and an up-pipe E. The return bend 5 is connected to a sumppipe I, having a cap 8 at its lower end.

A chain 9 is connected to drive the special engine, I from a powertake-off I0 of the truck.

The. special engine I and the truck 2 are both supplied with thenecessary radiators, fans, fan drives, belts, chains and gears, powertakeofi, carburetor means, electric spark systems and all necessarycontrols and other parts as anyone skilled in the art will understand. v

Figure 3 shows a modified form of U-tube, or return pipe, in which thehot gas goes down an outer down pipe 4* and comes up a smaller, innerpipe, 6'.

Figure 4 shows the down pipe 4- and the uppipe 6', and a p mp pipe 6-.

Figure 5 shows a base ll, supporting a crankshaft l2, with two crankpinsl2), 1-2, and a cylinder l3;

The cylinder l3- has a cylinder head l4 and a cylinder plate 15, closingthe water jacket of the cylinder. A piston I6 reciprocates in thecylinder I3 through action of connecting rod H, which connects thepiston 16 with the crankpin l2 of the crankshaft 12 The cylinder head [4has an automatic intake valve I8, normally held upon its seat by anintake valve spring Hi;

When the piston [6 moves away from the cylinder head, the suction opensthe intake valve l8, and permits the entrance of a charge of explosivemixture, composed of air mixed with fuel from a carburetor 2%. (SeeFigure 6.) A spark plug is shown at 23', of Figure 5.

Figure 6 shows the two cylinders E3 of the engine with intake pipes 33,connected to the carburetor 2B. (Figure 2 shows two exhaust pipes 2!,which join to form the. exhaust pipe 3, which is connected to, thedown-pipe 4 of the U-tube.)

Figure 6 also shows the joined intake pipes, 33 and the carburetor 20,which is equipped with the usual adjustments and the usual throttle.

Figure '7 shows a two to, one geared electric spark timer or distributor22, mounted; upon the engine to time the sparks at the spark plugs 23,and a sprocket 24 mounted upon the crankshaft l2 to receive the chain 9,from the sprocket of the truck power take-off. (See Figure 1'.)

Figure 7 also shows an exhaust valve 25, whose stem 25 is guided in anexhaust valve stem de 21.

The exhaust valve, 25' is resiliently held against its seat by anexhaust valve spring 23. All 8X- haust valve Washer 29 rests against ashoulder on the valve stem 26;

An exhaust valve spring cover tube 38 screws or has other properattachment with the, exhaust valve stem guide 27'; and an exhaust valvespring stop 3! screws or has other proper. attachment to the cover tube36, and permits the free movement of the valve stem 26 through it.

Thus, the exhaust valve spring 23 bears against the spring stop 31 atits outer end and against the'exhaust valve washer 29- at its inner end,holding the exhaust valve 25 resiliently upon its seat i c pExhaustconnecting pipes (Figure 2)- connect'to exhaust valvepockets 32. (Figure7.) l It is understood that all connections, tubes, wiresycontrolsandadjustments for fuel and spark systems-are properly made andeasilyoperated, and all proper lubrication where required is provided for, asanyone skilled in the'art will understand. I

The operation of my special internal combustion engine takes place asfollows: The positions A, B, C, D, indicate the location of the top ofthe piston I6 at different points in its movements, as will be explainedbelow.

At A the piston is on up-center and is just about to move downwardtoward the crankshaft l2.

As the piston moves downward it sucks an explosive charge through thecarburetor '20, the intake pipe 33, and the intake valve IS. Theexplosive charge consists of air which is mixed with the proper amountof fuel as it passes through the carburetor 20.

When the piston l6 uncovers the exhaust port 34 in the cylinder wall,the suction merely acts to pull the exhaust valve 25 more firmly downupon its seat.

When the piston I6 has reached its down center, as at B, the entirecylinder l3 (theoretically at least) will be full of explosive mixture.

As the piston l6 begins its upward stroke toward the intake valve l8, itbegins to compress the explosive mixture in the cylinder.

When this compression of the explosive mixture is great enough to forceopen the exhaust valve 25 against the pressure of the exhaust valvespring 28, the explosive mixture will begin to pass out of the cylinder,through the exhaust port 34, the exhaust valve pocket 32, the exhaustconnecting pipes 2|, and the exhaust pipe 3 to the down-tube 4 of theU-tube.

As the piston l6 reaches the position D, it begins to shut off thecylinder exhaust port 34; but it still continues to force the explosivemixture out of the port 34 and on out through the exhaust valve 25 tillthe piston l6 reaches the position C, where the exhaust port 34 iscompletely shut off by the piston l6.

As the piston [6 moves from C to A it compresses the remanent of theexplosive charge that is trapped in the cylinder above the exhaust port34 and, when the position A is reached, the spark occurs at the sparkplug 23 (Figure 5) and explodes the remanent of the explosive chargethat has been compressed in the cylinder I3.

The exact timing of the spark, is, of course, adjustable, as anyoneskilled in the art will understand.

As the explosion occurs the piston l6 moves downward toward thecrankshaft I2, and when it reaches the position C and begins to uncoverthe exhaust port 34 in the cylinder walls, the pressure of the explosioncauses the fire of the explosion to pass out of the exhaust valve 25 toignite the raw charge of explosive mixture in the exhaust valve pocket32, the exhaust connecting pipe 2|, the exhaust pipe 3, and thedown-pipe 4 of the U-tube.

The raw explosive mixture formerly forced out of the cylinder throughthe exhaust valve 25 by the upward movement of the piston I6 is therebyignited in the exhaust passages to force the fire and the heat and. theexploded gas' on through the U-tube, thus heating theoil well.

Thepiston I6 travels on down to thepositidn B and on the returnstrokeexpels the remanent of the exploded gas from the cylinder out of theexhaust valve 25 and into the exhaust passages as soon as the return ofthe piston It creates enough pressure to open the exhaust valve 25. a

After the exhaust port 34 is shut off bythe pistonllG, as at C, itscontinued movement compresses the remanent of exploded gas trapped inthe cylinder abovetheport 34, but aftera short downward movement ofthelpiston it on the next downward stroke, the piston IE will again suckin a new charge through the carburetor 20, the intake pipe 33, andintake valve l8, and the entire cycle will be repeated.

Thus, it will be seen that the raw explosive mixtur is first forced intothe exhaust passages of my engine, where it remains, un-compressed, tillthe fire of the explosion of the remanent of the charge trapped in thecylinder l3 above the port 34, comes through the port 34 and the exhaustvalve 25 and ignites and explodes the uncompressed charge in the exhaustpassages. The force of the explosion in the exhaust passages and thedownward movement of the piston I6 combine to keep the exhaust valve 25on its seat for at least a part of the downward stroke of the piston l6.

Since the charge in the exhaust passages is not compressed, unless asingle, open, and submerged down pipe is used, the explosion pressurewill not be high enough to rupture any of the exhaust passages, but itwill be high enough to force the hot, burning products of combustiondown into the well to heat it.

However, since the explosions are intermittent, they will tend to movethe hot gas through the U-tube intermittently.

For this reason I also provide a suction device 35, shown in Figure 1,and connected with the up-pipe 6 of the U-tube, and properly operatedand driven from the power take-off of the truck or otherwise. Thissuction device should be of proper capacity and suction to tend to keepthe hot gas moving through the U-tube even between th explosions of myspecial internal combustion engine.

It will, of course, be seen that the amount of heat sent down the U-tubecan be controlled by proper adjustment of both the carburetor throttleand the timing of the spark of my special engine and also by control ofthe speed of the truck engine and its power take-off which drives myspecial heat engine, and the suction device.

Having now described my invention, what I claim as new and desire toprotect by Letters Patent, is as follows:

1. A heat engine for supplying heat to an oil well comprising; a pipeextending into said well; a cylinder above said well; a pistonreciprocated in said cylinder; a carburetor communicating with saidcylinder to supply an explosive raw gaseous mixture thereto; an inletvalve for preventing return of the mixture to the carburetor from saidcylinder; a discharge port in the cylindrical wall of said cylinderpositioned to be covered by said piston as it approaches the head end ofsaid cylinder, said discharge port communicating with said pipe; anoutwardly opening outlet valve in said discharge port; a spring forreturning said outlet valve to its seat, said spring being ofinsufficient strength to retain the 2. A-heat engine for supplying heatto a. pipe extending: into an oil well for melting the paraffine in thelatter, comprising: a cylinder having a head in one extremity; a; pistonin saidzcylinder; an inlet valve in. said head for admitting rawcombustion gases" to said cylinder; an outlet port in the cylindricalwall of said cylinder adjacent saidhead communicating with said pipe,

said port-being so positioned that .it will remain open for the, mainportion of the compression stroke" of said piston; toallow thev majorityof the. raw gas to be forced into said pipe by said piston and sezthatitwillbe. closed by said piston 10 to-trapthe remainder oi the gasinrsaidcylinden for compression purposes; and an ignition device forexploding said-1 remainder.-

ALFRED PICK.

